Johnson posted a photo of himself in a hospital bed on Instagram but didn’t reveal what procedure he had. He wrote, “Ima Bounce Back.”
The Steelers selected Johnson in the third round last spring.
Johnson dealt with a concussion and an illness during his rookie season, the only times he was listed on the Steelers’ injury report. He played all 16 games, starting 12, and saw action on 66 percent of the offensive snaps.
Johnson made 59 catches for 680 yards and five touchdowns. He also averaged a league-leading 12.4 yards on 20 punt returns and scored a touchdown.